A permanent urban boundary to contain Melbourne’s sprawl is part of the new blueprint to deal with the city’s booming population, now forecast to hit almost eight million by 2051.

The government’s new Plan Melbourne declares the need for a ”clear statement” on the boundary. But the final line could be different to the existing limits, with the plan setting up a mechanism to determine it.

The views of councils, the city’s physical features and boundaries formed by major infrastructure are among the factors that will be considered by the new Metropolitan Planning Authority, which will implement the new strategy.

The plan includes sweeping revisions to Melbourne’s population, now at 4.3 million, with the city expected to hit 7.7 million people by 2051, up from 6.5 million forecast in the draft of the plan only seven months ago.

Beyond limiting urban sprawl, the plan also proposes a boost in growth in Victoria’s regional centres to accommodate the extra numbers.

It also includes the Napthine government’s big infrastructure projects, such as the East West Link and the Melbourne Rail Link, including the airport rail link.

Premier Denis Napthine said the state’s population was growing at an annual rate of 2 per cent, compared with 1.8 per cent in the rest of the country. But he argued Melbourne could grow while at the same time protecting its treasured liveability.

Planning Minister Matthew Guy said the strategy provided a solid foundation to meet the challenges of a city of 7.7 million. ”This is a document that will define the way not just Melbourne, but the entirety of Victoria, grows into the future,” he said.

But opposition planning spokesman Brian Tee said Mr Guy had ignored the 10,000 Victorians who gave their views for the strategy, and had rewritten the plan to justify ”a dodgy East West tunnel”.

”Last month’s state budget had no substantive funding for anything else in the plan because it has all been blown on Denis Napthine’s expensive dud tunnel,” he said.

The planning strategy, which aims to establish a direction for the next 40 years, also:

■ Expands the central city with the aim of becoming Australia’s largest commercial and residential centre by 2040. This includes urban renewal projects at Fishermans Bend and E-Gate, and a bigger employment cluster at Parkville.

■ Proposes 20-minute neighbourhoods – where facilities and jobs are only a 20-minute trip from home.

Planning expert Roz Hansen, who headed Mr Guy’s advisory committee and resigned in protest over public service interference, described the plan as ”very disappointing”. She said there was very little change from the October draft, with the main inclusions being the recent announcements by the government, such as the big transport projects.

She said there were many lost opportunities, such as initiatives for housing affordability, planning neighbourhoods for increased housing choice and more services. There was also a reluctance to improve metropolitan bus services in middle and outer suburbs.

Planning Institute of Australia state president Brett Davis was ”cautiously optimistic” about the planning blueprint. He welcomed the airport rail link and expanding of an employment cluster at Parkville. But he raised concerns about prioritising the East West Link.

”There does seem to be some retrofitting of policy to match some of the announcements that have just come out,” he said. ”The East West link … we wouldn’t identify as a priority project.”